The present invention relates to an industrial robot control device for controlling a number of machines provided in a single production line. More particularly, the invention relates to an industrial robot control device for use in an automobile manufacturing line for instance, which is capable of preventing incorrect or improper operations of the machines due to a voltage drop in a power source, which occurs when a plurality of machines including the industrial robots are driven simultaneously.
Recently, there has been an increasing number of situations in which a large number of robots are installed in a single production line. In an automobile welding and assembling line, for example, there are provided a large number of industrial robots having spot welding guns and a large amount of electrical power is needed for such spot welding operations and robot drive control.
Therefore, when the various machines in the line are driven simultaneously, there may occur a risk of imperfect welding or incorrect robot operations due to a temporary drop in the power supply voltage.
This can be avoided by the provision of equipment which has a power supply capacity such that the supply voltage drop will not go below a predetermined value even if all the machines are actuated simultaneously. However, this approach to solving the problem is very costly.
As described above, the prior art device is disadvantageous due to imperfect welding or incorrect robot operations if all the machines in a line are actuated simultaneously since, from considerations of economy, it is generally necessary to employ power supply equipment having a capacity less than that required for sufficiently driving all the machines in the line sufficiently.